Abstract

Novel materials whose properties are influenced by the presence of d- and/or f-electrons have been of sustained interest to the condensed matter community. Innovative material syntheses, together with thermodynamic, transport and cutting-edge spectroscopy experiments have been revealing an intriguing array of properties. These have also brought to fore theoretical challenges posed by the presence of strong electronic correlations. Large-scale first-principle computational approaches have been valuable in deciphering experimental findings and predicting new results. I will first discuss basic ideas underlying dynamical mean field theory (DMFT), and then the self-consistent embedded dynamical mean-field theory (eDMFT) approach that we use. I will show how we depict the emergent many-body states in the nickelates and our proposed correlation-temperature (U-T) phase diagram. The key features are a low-T Fermi liquid (FL) phase, a high-T Curie-Weiss regime, and an antiferromagnetic phase in a relatively small U-T region.